Ethylene is known to mediate a variety of growth phenomena in plants. See generally Fritz et al. U.S. Pat. No. 3,879,188. This activity is understood to be achieved through a specific ethylene receptor in plants. Many compounds other than ethylene interact with this receptor: some mimic the action of ethylene; while others prevent ethylene from binding and thereby counteract its action.
Many compounds that block the action of ethylene do so by binding to the ethylene binding site. Unfortunately, they often diffuse from the binding site over a period of several hours. See E. Sisler and C. Wood, Plant Growth Reg. 7, 181-191 (1988). These blocking compounds may be used to counteract ethylene action. However, a problem with such compounds is that exposure must be continuous if the effect is to last for more than a few hours.
Photoaffinity labeling has been used in biological studies to label binding sites in a permanent manner—usually by generating a carbene or nitrene intermediate. Such intermediates are generally reactive and react rapidly and indiscriminately with many compositions. A compound already bound, however, would react mostly with the binding site. In a preliminary study, it was shown that cyclopentadiene was an effective blocking agent for ethylene binding. See E. Sisler et al., Plant Growth Reg. 9, 157-164 (1990). Methods of combating the ethylene response in plants with diazocyclopentadiene and derivatives thereof are described in U.S. Pat. No. 5,100,462 to Sisler et al. U.S. Pat. No. 5,518,988 to Sisler et al. describes the use of cyclopropenes having a C1 to C4 alkyl group to block the action of ethylene.
Notwithstanding these efforts, however, there remains a need in the art for additional methods providing improved plant maturation and degradation regulation as well as those for counteracting ethylene-induced processes in agricultural produce and/or horticultural products.